| 摘要 |
The invention relates to a radiation-emitting semiconductor diode in the InGaP/InAlGaP material system having a barrier (4A) for charge carriers situated between the active layer (2) and one of the cladding layers (1, 3). Such a diode has an emission wavelength between 0.6 and 0.7 mu m and is particularly suitable, when constructed as a diode laser, for serving as a radiation source in, for example, a system for reading and/or writing of optical discs, also because of an increased efficiency. A disadvantage of the known diode is that it is still insufficiently capable of providing a high optical power, and that it cannot be manufactured with a high yield and a satisfactory reproducibility. In a diode according to the invention, the barrier (4A) comprises only a single barrier layer (4) of AlP. Such a diode is found to have a surprisingly high efficiency as well as a particularly long useful life. The efficiency of the diode is approximately 30 % higher than that of a comparable diode without a barrier layer (4). The life of a diode according to the invention is very long, for example, 4,000 hours. Since the problem of controlling the composition of the barrier layer (4) is nonexistent in providing the AlP, the diode according to the invention can be manufactured with a good reproducibility and high yield. The AlP barrier layer (4) preferably has a thickness smaller than 5 nm, for example 2.5 nm. It is highly suprising that such a very small thickness of the barrier layer (4) is still accompanied by an excellent effectiveness as a barrier (4A). |
